Even the keenest cricket fan has to admit that the 2009 Ashes triumph at the Oval felt less hysterical and special than the 2005 victory at the same ground, and various theories have been advanced to account for this: the cricket was less impressive than four years ago; a second victory in successive series can not match the impact of a first for 18 years; and Team England tempered its celebrations to reflect the recession.

The simplest explanation, though, is that these Ashes felt less like a shared national moment because fewer of the nation shared it. The previous series, broadcast on Channel 4, had average audiences of 3 million, with 7 million watching the climax of the final match. The 2009 encounters, transmitted by Sky, attracted a regular 850,000, rising to 1.9million at the denouement.

It's true that two million viewers watched the Sunday-night terrestrial highlights on Five, but unless these were all new viewers, at least three million cricket fans have gone missing. Even more worryingly for Sky, this series finished on a Sunday, when TV viewers should be more readily available than on the Monday afternoon when England last won.

So the impact of moving a sport from free-to-view to pay-to-play is now measurable, and the government committee considering whether some sporting events should be protected for terrestrial broadcasters will surely look hard at these figures.

The issue is complex because there is little doubt that Sky's coverage is far more inventive than the BBC's used to be and at least matches that of Channel 4. Newspapers and Test Match Special (with new signings Phil Tufnell and Matthew Hayden outstanding) have also raised their game. But the fact is that viewers who want to watch test cricket are now missing it and, despite the financial boon to English cricket from the Sky cash, cricket must lose from this relative invisibility.

No matter how well Sky covers the hundreds scored, the figure of the missing 3 million stands ominously on the scoreboard.